This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 10-030245, filed Feb. 12, 1998, the entire contents of which are incorporated herein by reference.
The present invention relates to an information storage medium having multiple information layers and a multi-purpose information processing apparatus, which are effective in use in a recording/reproducing apparatus for DVD (Digital Video Disk), a transmitting/receiving apparatus and so forth.
As well known, recently, due to the advancement of the digital signal compression technology, a technology of digitizing video information has advanced in the MPEG (Moving Picture Image Coding Experts Group) or the like to allow video information to be handled in a PC (Personal Computer) environment and multimedia environments have been improved.
At present, however, the affinity between the PC environment and video information is very poor for the following two reasons:
1. Difference in the amounts of information to be processed . . . the problem of FAT (File Allocation Table) 16 and hindrance of the PC environment by video information processing.
2. Difference in the adequate information processing schemes necessity to secure continuous recording and reproduction.
That is,
1. Difference in the Amounts of Information to be Processed
At present, PCs often use FAT 16 as a file system for HDD (Hard Disk Drive) in view of compatibility with old PC data. FAT 16 permits a maximum of 2 GB (Giga bytes) per partition. When the data transfer rate of MPEG 2 is 5 Mbps (Mega bits per second), for example, only 53 minutes at a maximum can be recorded per partition. In recording two and half hours of a movie in an HDD of FAT 16, therefore, it is necessary to make recording over three partitions, making it difficult for a general-purpose PC system which does not use RAID (Redundant Arrays of Inexpensive Disk) to do automatic recording.
In the case of recording and editing video images, all of xe2x80x9crecording/editing application softwarexe2x80x9d, xe2x80x9cstandard template information for edition and processingxe2x80x9d and xe2x80x9cvideo information to be recorded or editedxe2x80x9d should be recorded within a PC environment, thus significantly suppressing the memory space of the PC environment. After a work of recording or editing video information is completed, the remaining memory space becomes small so that execution of another application software may be hindered.
2. Difference in the Adequate Information Processing Schemes
It is essential to secure a continuous operation for recording and reproducing video information. But, the seek time of the optical head of an information recording/reproducing apparatus is very long. When video information which is located here and there on an information storage medium is sought one piece after another and sequentially reproduced by the optical head, there is a case where a reproduced image is stopped during the seek time.
When conventional PC information and video information are recorded together on the same information storage medium, video information is very likely to be recorded dispersively on the information storage medium.
When a file is changed in a PC environment, the entire file data after the change is recorded again in an empty area on a information storage medium. The re-recording position on the information storage medium at this time is determined regardless of the recording position of file data before the change.
Because the amount of video information is vast as mentioned above, when a file is changed by the same method, re-recording takes considerable time. In the case of video information, therefore, it is desirable to re-record only a to-be-changed portion at the position before the change took place, without changing the position of an unchanged portion on the information storage medium. As this environment is not provided, however, it is very hard to handle video information in the PC environment.
The present invention has been made in view of the above situations, and it is a primary object to provide an information storage medium which has multiple layers and gives general addresses to this multiple information layers to thereby facilitate information handling, and a signal processing apparatus for that medium.
It is another object of this invention to provide a video information processing method effective in a PC environment, which prevents a PC environment from being hindered by the use of video information and can edit and process video information in a short period of time while securing a continuous operation at the time of recording or reproducing video information.
It is a further object of this invention to provide an optical system for the above video information processing.
To achieve the above objects, this invention records, on an information storage medium having multiple information layers including a recording layer capable of making recording with condensed light, general addresses for the multiple information layers and information indicating a condition for setting the general addresses.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.